%A LIU Yan-Lan, GUO Xian-Shi, ZHANG Xu-Cheng, MA Ming-Sheng, WANG Hong-Kang %T Effects of planting density and fertilization on dry matter accumulation, yield and water-fertilizer utilization of dryland potato %0 Journal Article %D 2021 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2021.04100 %P 320-331 %V 47 %N 2 %U {https://zwxb.chinacrops.org/CN/abstract/article_7046.shtml} %8 2021-02-12 %X

It is important to increase potato production and the natural resource utilization efficiency in dryland farming system. A field experiment was conducted using Longshu 10 with three planting modes from 2017 to 2019, including farmer mode (CK), the mode with high yield and efficiency (YE), and higher yield mode (HY). The leaf area index (LAI), SPAD, photosynthetic rate, accumulation and remobilization of dry matter, water use efficiency (WUE) and fertilizer use efficiency (FUE) was investigated. The results showed that LAI and SPAD were increased in YE and HY compared to CK, and it was more significant in 2017 when there was less rainfall. Meanwhile, less reduction in LAI and SPAD after tubers enlargement resulted in an increase of canopy photosynthetic rate by 29.9%, 34.7% (in 2018 and 2019), and 40.2%, 50.5% (in 2018 and 2019) during the expanding stage and starch accumulation stage, respectively. Average aboveground dry matter in YE and HY was higher than CK by 123.1% and 118.5% in the enlargement stage due to higher LAI and photosynthetic rate. The contribution rate of assimilation after potato tuber enlargement in YE and HE was higher than CK by 22.56% and 19.29%, resulting in an average potato production increase of 47.93% and 47.78%, and average water use efficiency increased by 77.59% and 75.85%, respectively. YE and HY advantaged in tuber production and income improvement. Compared with CK, the net income increased by 7330.3 Yuan hm-2 and 6024.6 Yuan hm-2 in 2017 to 2019, respectively. The accumulation of N, P, and K was significantly enhanced due to large population canopy and high plant biomass accumulation. Compared to CK, N and P use efficiency, and the harvest index of N and P was increased under YE mode by 15.21%, 17.20% and 3.85%, 7.79%, respectively, and the N use efficiency was increased by 12.37% under HY mode. WUE, N, and P use efficiency of YE mode was higher than HY by 2.05%, 2.53%, and 23.41%, respectively, and the net income increased by 1305.7 Yuan hm-2. Therefore, replacement of slow-release urea with organic manure by 40% and improvement of planting density with 60,000 plants hm-2 in YE mode potentially increased in water use efficiency, nutrient use efficiency, high canopy photosynthetic rate maintenances, and remobilization of dry matter from stem and leaf to tubers. In conclusion, YE as a high tuber production and resource use efficiency planting mode, is recommended in semi-arid areas with black-film mulched potato cultivation regime.